--- src/VBox/Additions/Makefile.kmk.orig	2020-07-10 02:49:58.000000000 +1000
+++ src/VBox/Additions/Makefile.kmk	2020-08-22 15:50:59.010676000 +1000
@@ -52,6 +52,9 @@
   include $(PATH_SUB_CURRENT)/x11/Makefile.kmk
  endif
 
+ ifeq ($(KBUILD_TARGET),bsdsunix)
+  include $(PATH_SUB_CURRENT)/bsdsunix/Makefile.kmk
+ endif
  ifeq ($(KBUILD_TARGET),freebsd)
   include $(PATH_SUB_CURRENT)/freebsd/Makefile.kmk
  endif
@@ -163,6 +166,18 @@
 	VBoxDarwinAdditions-amd64.dmg=$(VBOX_PATH_ADDITIONS.darwin.amd64)/VBoxDarwinAdditions.dmg
 endif
 
+# BSDSUniX
+ifdef VBOX_WITH_ADDITIONS_ISO.bsdsunix.amd64
+ VBOX_PATH_ADDITIONS.bsdsunix.amd64 = $(PATH_OUT_BASE)/bsdsunix.amd64/$(KBUILD_TYPE)/bin/additions
+ GUESTADDITIONS_FILESPEC.bsdsunix.amd64 = \
+	VBoxBSDSUniXAdditions-amd64.tbz=$(VBOX_PATH_ADDITIONS.bsdsunix.amd64)/VBoxBSDSUniXAdditions.tbz
+endif
+ifdef VBOX_WITH_ADDITIONS_ISO.bsdsunix.x86
+ VBOX_PATH_ADDITIONS.bsdsunix.x86 = $(PATH_OUT_BASE)/bsdsunix.x86/$(KBUILD_TYPE)/bin/additions
+ GUESTADDITIONS_FILESPEC.bsdsunix.x86 = \
+	VBoxBSDSUniXAdditions-x86.tbz=$(VBOX_PATH_ADDITIONS.bsdsunix.x86)/VBoxBSDSUniXAdditions.tbz
+endif
+
 # FreeBSD
 ifdef VBOX_WITH_ADDITIONS_ISO.freebsd.amd64
  VBOX_PATH_ADDITIONS.freebsd.amd64 = $(PATH_OUT_BASE)/freebsd.amd64/$(KBUILD_TYPE)/bin/additions
@@ -298,6 +313,8 @@
 	$(GUESTADDITIONS_FILESPEC.os2.x86) \
 	$(GUESTADDITIONS_FILESPEC.linux.x86) \
 	$(GUESTADDITIONS_FILESPEC.linux.amd64) \
+	$(GUESTADDITIONS_FILESPEC.bsdsunix.x86) \
+	$(GUESTADDITIONS_FILESPEC.bsdsunix.amd64) \
 	$(GUESTADDITIONS_FILESPEC.freebsd.x86) \
 	$(GUESTADDITIONS_FILESPEC.freebsd.amd64) \
 	$(GUESTADDITIONS_FILESPEC.haiku.x86) \